One

One is a mysterious person whose affiliations are still unknown.

Appearance
Nothing is known of her appearance as she didn't appear yet.

Personality
Nothing is known of her personality as she didn't appear yet.

History
Nothing is much known about One except for the fact that she was a member of a group that wished to remove the darkness that envelops that world. Her allies include Zero.

Hidden Transmission
One was sent a hidden transmission from Zero, telling her all the things that have happened since he was away.

Magic and Abilities
Nothing is known of Zero's abilities. It is true though, that he possesses something, guaranteeing his membership to the group he's part of.

Zero
Main Article: Zero

One seems to be unaware of Zero's feelings for her. However, the two of them were the best of friends due to their time together in doing their missions.